Hitherto, various movable mechanisms are provided for pop-up of a part, including, for example, those by motor drive (e.g. JP-A-9-211572 (“JP-A” means unexamined published Japanese patent application)), those by coil spring drive (e.g. JP-A-2002-304241), and those by wire spring drive (e.g. JP-A-63-276749).
In the above patent document 1, the motor is used as a driving source, and a flush apparatus is popped up by means of an intermediate gear and a solid cam. In patent document 2, the coil spring is used as a driving source, and a large stroke is obtained by combining the spring with an auxiliary pin that also serves as a guide in the pop-up direction. In patent document 3, a repulsive force of the wire spring provided at the end of the apparatus is used as a driving source, and the part is popped up by combining the spring with a lock releasing member.
While the apparatus using the movable mechanism is being made lightweight in recent years, the movable mechanism itself is required to be lightweight and have a simple mechanism.
However, in patent document 1 using a motor as a driving source, since the stroboscope is popped up by taking advantage of the driving power of the motor by means of the gear and solid cam, the occupation area of the mechanism becomes inevitably large with a complex mechanism. Further, while the mechanism is attempted to be lightweight and simple in the movable mechanisms taking advantage of the coil spring or wire spring as the driving source as described in patent document 2 and patent document 3, a sufficient action force cannot be obtained, although a large stroke is readily obtained by using the coil spring as the driving force. On the contrary, while a sufficiently large action force can be obtained by using the wire spring, a large stroke may be hardly obtained. Therefore, a driving mechanism exhibiting large action force and stroke with a light and simple mechanism is desired.
Other and further features and advantages of the invention will appear more fully from the following description, taken in connection with the accompanying drawing.